Most of wigs are formed by implanted artificial hairs or natural hairs, such as human hairs, in a wig base which is formed of an artificial skin made of synthetic resin, such as urethane, a net with meshes of synthetic fibers, or a combination of the artificial skin and the net.
Recently, among wigs made of the same amount of hairs (artificial or natural hairs) implanted, voluminous wigs tend to be required.
For this reason, the hairs implanted in the wig base are designed to be curled with a predetermined curl diameter (that is, the hairs are curled hairs). Such wigs are in widespread use.
The curled hairs with a relatively larger curl diameter tend to stand up substantially vertically from the wig base, and then to expand gradually transversely along the curl diameter, easily enhancing the voluminous feeling. The hairs with the larger curl diameter, however, have longer parts standing up from the base, which tends to cause the hairs to easily fall over due to a small external force, for example, even moderate wind. As a result, in some cased the desired voluminous feeling cannot be obtained.
On the other hand, the hairs with the smaller curl diameter have shorter parts substantially vertically standing up from the base, which can effectively prevent the hairs from falling over due to the small external force. However, the small curl diameter often makes it difficult for the hairs to obtain the desired voluminous feeling.
Patent Document 1 discloses a wig having hairs with different curl diameters mixed at a predetermined rate and implanted to improve its voluminous feeling.